In 1957 Noam Chomsky published Syntactic Structures, expressing views characterized as constituting a “revolution” in linguistics. Chomsky proposed that the proper subject matter of linguistics is not the utterances of speakers, but what speakers and listeners know. To that end, he theorized that what they know is a system of rules that underlie actual performance. This theory became known as transformational grammar. In subsequent versions of this theory, rules continued to play a dominant role. However, in 1980 Chomsky began a second revolution by proposing the elimination of rules in a new theory: the principles-and-parameters approach. Subsequent writings finalized the abandonment of rules. Given the centrality of rules to cognitivism, this paper argues that Chomsky’s second revolution constitutes a departure from cognitivism.